Five of the 789 professional athletes infected with COVID-19 were later found to have suffered from heart disease in the largest study to date on the cardiac impact of the virus in sports.
According to data published Thursday in JAMA Cardiology, doctors affiliated with six US leagues followed the 789 infected players last year between May and October.
Before returning to play, the athletes underwent three non-invasive tests that tracked their heart rate, performed an ultrasound of their heart and measured a blood protein that could be a signal of heart damage. Thirty athletes had abnormal test results and were referred for a cardiac MRI. Doctors diagnosed five cases of inflammatory heart disease (0.6% of the total), including three cases identified as myocarditis and two as pericarditis.
Dr. David Engel, a cardiologist at Columbia University’s Irving Medical Center and one of the lead authors, said the results are consistent with current assessments that COVID-19 heart damage correlates with the severity of symptoms. The study included infected athletes who were both symptomatic and asymptomatic. All five cases of heart disease included symptoms that “exceeded the empirical definitions of mild COVID-19 disease,” according to the paper.
Doctors are still waiting for even bigger data sets to be compiled by the Big Ten and NCAA sports conference. Individual universities published data from their own projections with mixed results. A study by Ohio State University came in the fall, when researchers found that four out of 26 athletes – or 15% – had signs of myocarditis after COVID-19. A later study by the University of Wisconsin found only two cases out of 145 athletes.
Myocarditis is a rare but known effect of viral infections, including those that cause the common cold, H1N1 flu, or mononucleosis. Left undiagnosed and untreated, it can cause heart damage and sudden cardiac arrest, which can be fatal.
Concerns about this and other heart conditions fueled initial debates about playing sports during the pandemic, especially last summer, in connection with college football. Engel attributed some of this concern to confusion over how to interpret studies that used cardiac MRI to identify the disease.
The professional sports leagues that contributed data to JAMA Cardiology – NBA, WNBA, NFL, NHL, Major League Baseball and Major League Soccer – followed a standardized screening procedure recommended by the American College of Cardiology. This included blood tests, an electrocardiogram and a resting echocardiogram or cardiac ultrasound. Subsequent tests and, finally, the diagnosis, were based on anomalies of the initial screening.
“There has been a lot of controversy over how to interpret these cardiac MRI studies and really what the significance of these findings was,” Engel said. “This study had a very clinically relevant approach. Patients who tested positive went through the recommended screening at the American College of Cardiology. Only after there were anomalies did I continue the subsequent tests. Using this step-by-step approach, we found what we considered to be quite low clinically relevant incidents of myocarditis and pericarditis. “
Ten of the doctors involved in the study revealed that they had received financial compensation or that they were employed by one of the leagues or associations involved. Engel is the NBA’s consulting cardiologist.
The five players diagnosed with heart disease, who were not identified for the purpose of the study, were all subjected to three to six months away from the sport and will continue to be tested to determine the long-term effects of the disease on their physical condition. Previously, the American College of Cardiology recommended eliminating screening for athletes who had asymptomatic or mild cases, while maintaining the same screening process for those who had moderate or severe symptoms.
“What was reassuring was that all the athletes who went through the screening, 784 out of 789, managed to return safely to the game,” Engel said. “This was unknown. At the beginning of the pandemic, when these answers were not known … we were able to demonstrate that, through a rigorous and systematic approach to screening, we were able to achieve a safe return to the game.”
In a joint statement, the six leagues said in part: “As with other lessons that professional sports have learned about COVID-19, the results of this study are widely shared to continue to contribute to growth. knowledge about the virus – a commitment that we collectively share with each other and our players for the benefit of society beyond sport. “
The results of the study seem to be good news for athletes who have suffered from COVID-19, said co-author Dr. Jonathan Kim, a sports cardiologist at Emory University in Atlanta who also works as a team cardiologist for the Atlanta Falcons.
“All four major sports are done by 2020, all eventually returning to one season – including those athletes who were included in this register – and some sports, such as the NBA, have now moved into a new season,” he said. Kim told Kaiser Health News. “Those athletes are obviously still playing and doing well.”
The study did not shed light on what could happen in the long run to those players who have been diagnosed with heart inflammation. These will continue to be monitored with MRIs to see if the effects fade over time.
“Only time will tell if in five years we will have an epidemic of failed hearts,” said Dr. Robert Bonow, a cardiologist at Northwestern University and editor of JAMA Cardiology, which was not affiliated with the study. “But I think it’s unlikely.”
The results of two future studies on the possible COVID-cardiac link are expected to be published soon, pending peer review.
Paula Lavigne, Mark Schlabach and Kaiser Health News reporter Markian Hawryluk contributed to the report.